Source for gnu.CORBA.SocketRepository

   1: /* SocketRepository.java --
   2:    Copyright (C) 2005 Free Software Foundation, Inc.
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version. */
  37: 
  38: 
  39: package gnu.CORBA;
  40: 
  41: import java.net.Socket;
  42: import java.net.SocketException;
  43: import java.util.HashMap;
  44: import java.util.Iterator;
  45: import java.util.Map;
  46: 
  47: /**
  48:  * This class caches the opened sockets that are reused during the
  49:  * frequent calls. Otherwise, some CORBA applications may spend
  50:  * up to 90 % of the working time just for closing and opening the sockets.
  51:  *
  52:  * @author Audrius Meskauskas, Lithuania (AudriusA@Bioinformatics.org)
  53:  */
  54: public class SocketRepository
  55: {
  56:   /**
  57:    * The socket map.
  58:    */
  59:   private static HashMap sockets = new HashMap();
  60: 
  61:   /**
  62:    * Put a socket. This method also discards all not reusable sockets from
  63:    * the map.
  64:    *
  65:    * @param key as socket key.
  66:    *
  67:    * @param s a socket.
  68:    */
  69:   public static void put_socket(Object key, Socket s)
  70:   {
  71:     synchronized (sockets)
  72:       {
  73:         sockets.put(key, s);
  74:         gc();
  75:       }
  76:   }
  77: 
  78:   /**
  79:    * Removes all non reusable sockets. As it is private,
  80:    * we know we call from the synchronized code already.
  81:    */
  82:   private static void gc()
  83:   {
  84:     Iterator iter = sockets.entrySet().iterator();
  85: 
  86:     Map.Entry e;
  87:     Socket sx;
  88: 
  89:     while (iter.hasNext())
  90:       {
  91:         e = (Map.Entry) iter.next();
  92:         sx = (Socket) e.getValue();
  93: 
  94:         if (not_reusable(sx))
  95:           iter.remove();
  96:       }
  97:   }
  98: 
  99:   /**
 100:    * Return true if the socket is no longer reusable.
 101:    */
 102:   static boolean not_reusable(Socket s)
 103:   {
 104:     return (s.isClosed() || !s.isBound() || !s.isConnected() ||
 105:         s.isInputShutdown() || s.isOutputShutdown());
 106:   }
 107: 
 108:   /**
 109:    * Get a socket.
 110:    *
 111:    * @param key a socket key.
 112:    *
 113:    * @return an opened socket for reuse, null if no such available or it is
 114:    * closed, its input or output has been shutown or otherwise the socket is not
 115:    * reuseable.
 116:    */
 117:   public static Socket get_socket(Object key)
 118:   {
 119:     synchronized (sockets)
 120:       {
 121:         Socket s = (Socket) sockets.get(key);
 122:         if (s == null)
 123:           return null;
 124: 
 125:         // Ensure that the socket is fully reusable.
 126:         else if (not_reusable(s))
 127:           {
 128:             sockets.remove(key);
 129:             return null;
 130:           }
 131:         else
 132:           {
 133:             try
 134:               {
 135:                 // Set one minute time out that will be changed later.
 136:                 s.setSoTimeout(60 * 1000);
 137:               }
 138:             catch (SocketException e)
 139:               {
 140:                 s = null;
 141:               }
 142: 
 143:             sockets.remove(key);
 144:             return s;
 145:           }
 146:       }
 147:   }
 148: }